CHICAGO -- Growing up with a severely disabled brother, Abby Brown felt less like a sister and more like a "third parent." Nigel, two years her junior, was born with a rare disease called linear sebaceous nevus syndrome that left him nonverbal and needing assistance to eat, dress and use the toilet.

As a child, Brown mourned the normal things she couldn't do like take family vacations or go to the mall, without her brother having a seizure while they were there.

As an adult, she nervously anticipates a time when she'll be in charge of his care.

"Where will he live when my parents are unable to take care of him?" wonders Brown, 21, a student at Nipissing University in North Bay, Ontario. "How will I manage taking care of aging parents, a disabled brother and children of my own? Will I ever find a partner who is willing to take on the responsibility of caring for my sibling with me?"

Brown's concerns are emblematic of the complex, lifelong and generally unsung relationships between disabled people and their siblings, who often log more years than anyone supporting their special-needs brothers and sisters without getting much support of their own.

"I find myself frequently in the ludicrous position of having to remind my friends, my colleagues and people who worship at the altar of family-centered services, that siblings are part of the family," said Don Meyer, director of the Seattle-based Sibling Support Project (siblingsupport.org) and creator of Sibshops, workshops that bring together the siblings of special-needs kids for recreational activities and peer support.

On his Facebook group Sibnet, an adult sibling support site with 1,300 members, Meyer is struck by how common it is for 40-year-olds to proclaim it's their first time meeting others who grew up with developmentally disabled siblings.

"People who work with families of kids with special needs would never let the parents wait 40 years to introduce them to their peers," Meyer said.

A sibling's need for support begins early, Meyer said, as growing up alongside a disabled child forges complicated feelings, from embarrassment to resentment to many forms of guilt. Some siblings feel pressure to be high achievers to balance the scale. Many yearn for the friendship of a "normal" sibling relationship.

The experience has its benefits too: Siblings of special-needs kids tend to develop early maturity and increased patience, diplomacy, tolerance and acceptance of difference, Meyer said. Many pursue helping professions, where they serve as powerful advocates for marginalized populations.

As parent caregivers get older, a sibling's role takes on added importance, and underscores the value of nurturing the siblings' relationship from childhood onward. About 75 percent of the 4.6 million developmentally and intellectually disabled people in the U.S. live with their families.

"If we affirm and validate their contributions as they grow up, we increase the chances that they will elect to remain lovingly involved in their (disabled siblings') lives," Meyer said.

Brown, who is studying to be a special education teacher, says the empathy and responsibility learned growing up alongside a disabled sibling "is a gift our siblings gave to us." She starts to cry when she tries to explain her love for Nigel, who, she warns any guy she dates, will always be No. 1.

"He is everything to me," she said. "I wouldn't trade him for the world."

That doesn't mean it has been easy.

Not knowing anyone who shared her situation and not wanting to add to her parents' stress, Brown felt particularly alone after returning home from college the first time, when the all-consuming nature of her brother's illness hit her "like a truck." She found solace in Sibnet, where she could converse with peers with similar concerns and learn how older siblings are dealing with the caregiving reality she will eventually confront.

Margaret Dickey, 32, a social worker living in South Bend, Ind., said "it's a little scary" to imagine a time when she eventually may have to care for her two autistic younger brothers. She's still trying to unravel the emotional consequences of their childhood together.

On the positive side, she learned to be flexible and roll with the punches during any number of unpredictable moments when her youngest brother might snatch a pair of bifocals from someone's face (when he was obsessed with bifocals) or compliment overweight people on their blubber (when he was eager to become fat).

But there were also dark moments when her other brother would lash out violently against himself or the family. Wanting to be strong for her parents, Dickey felt there was nowhere to direct her anger or sadness, so she kept it in, which sometimes felt like she was wearing a mask. In adulthood it continues to be difficult for her to set boundaries or identify and express her emotions, she said.

Dickey also said going to a counselor, or having someone validate or de-stigmatize her feelings, might have been helpful.

While most research has shown no negative long-term consequences of growing up with a special-needs sibling, there is a slight increased risk of depression and anxiety when the sibling has behavioral problems, said Julie Lounds Taylor, assistant professor of pediatrics and special education at Vanderbilt University.

One of the unique challenges many siblings face when the time comes for them to assume responsibility for their disabled brother or sister, is that they are thrown into it in crisis mode - such as when a parent's health suddenly declines - and are completely unprepared to deal with the day-to-day logistics of their sibling's condition.

"I am surprised that a lot of the information you would expect to flow down from parents to siblings, doesn't flow down," said Katie Arnold, executive director of the Sibling Leadership Network (siblingleadership.org), a national nonprofit that advocates for the interests of siblings through policy and peer support groups.

It helps if families start a dialogue early to get everyone on the same page about future caregiving plans, from special-needs trusts to medication schedules to guardianship decisions, Arnold said. Many parents are reluctant to have that conversation because they don't want to burden the siblings with such worries, but often it relieves worry among the "ultimate sandwich generation" anxious about juggling their own kids, aging parents and a disabled sibling.

While not all siblings want to participate in the care of a special-needs brother or sister, their involvement can be crucial to the family's well-being. Siblings often bring a fresh, peer-based perspective, less protective than that of parents, that encourages greater independence for the disabled sibling.

Tamar Heller, director of the Institute on Disability and Human Development at the University of Illinois at Chicago and a co-founder of the Sibling Leadership Network, said her younger sister, Daphne, who has cerebral palsy, had been languishing in a nursing home with diabetes and a MRSA infection when Heller had her transferred to a group home where, through support and motivation, she improved significantly. Heller said her parents told her the outcome "gave them 10 more years of life."

It can be good for the sibling relationship too.

After their mother passed away, Renee Silberman, 54, found her intellectually disabled older sister, Estella, an adult day program at a Jewish community center, where Estella works at a sandwich cafe and paints artwork that she sells at the center's fairs.

Though she wishes they could have a more equal sisterly relationship, Silberman, who lives in Lincolnwood, Ill., is grateful for the opportunity to get to know her sister in ways she hadn't as a child, including glimpses of acute emotional intelligence.

"I think I saved up all my noticing for now," Silberman said.

HOW PARENTS CAN HELP

What can parents of special-needs kids do to nurture their typically developing siblings? Vanderbilt University professor Julie Lounds Taylor offered some advice.

-Get them involved in Sibshops or other sibling support groups where they can spend time with other kids who have had similar experiences. There are 400 Sibshops in eight countries. (Go to siblingsupport.org.)

-Find ways to mitigate stress in the household generally, such as practicing mindfulness.

-Spend one-on-one time with the siblings doing things that have nothing to do with the disabled child.

-Have ongoing conversations at different life stages about how involved the sibling wants to be in the caretaking of the disabled person.

• Read more articles by ALEXIA ELEJALDE-RUIZ

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