Baby boomers who’ve cut the apron strings for adult children are more than twice as likely to be retired than boomers who haven’t, according to research from Hearts & Wallets.

Just 21 percent of boomers who support adult children are fully retired, while 52 percent of boomers whose children are independent were retired, according to the study.

Boomers supporting adult children total nearly eight million households with almost $4 trillion in assets, according to the Hingham, Mass.-based financial research firm.

“Parents supporting adult children wonder when, or if, their kids will ever become independent,” said Chris J. Brown, Hearts & Wallets partner and co-founder. “They worry about saving enough to have freedom to enjoy life as they age.”

According to the study, 51 percent said “saving enough for retirement” was their top financial concern. They also have high levels of anxiety over finances, with 53 percent agreeing they are somewhat or very uncomfortable "taking risks with investments by accepting volatility in the hope of getting a higher return."

In addition, 55 percent expressed concern about age discrimination by agreeing with the statement, “age discrimination prevents me from working as much as I would like.”

"Providing financial support to anyone, but especially to an adult child, can have tremendous consequences for retirement and estate planning,” said Brown. “Financial service firms would be wise to examine their client base for this trait and adjust product and service offerings to meet the needs of these nearly eight million boomer households.”

Hearts & Wallets based these findings from its 2015 study Dissecting the Baby Boomers, which analyzed data from over 5,500 U.S. households.