@RustyRaven@briongloid i've seen versions of this on my family and my mother wanted me to fit into this role when my dad died.
My cousin was adopted for this reason inmind basically an indentured servant to her adopted family. She had 4 older siblings with a ton of money that could easily afforded to put mom in a nursing home. Instead she had to do elder care until my auntie passed away from Alzheimer's. No family of her own, worked in retail for a day job to support herself.