Is it possible to use donor fat, like from a family member, for a BBL if you don't have sufficient?

 You cannot use someone else's fat for any procedure whether it is cosmetic or reconstructive. You're fat and tissues are unique to you. The body will reject someone else's fat as foreign.

Unfortunately that is not an option. Your body would reject it. There certainly are options for gaining enough weight for a BBL. My recommendation is that you find an ASPS board certified surgeon in your area who specializes in the BBL, and set up an in person consult. An in person consult with an ASPS board certified surgeon is the only way to determine the best route for your body and your goals. On some occasions patients who are devoid of the fat cells necessary for the BBL are asked to gain weight. This however is not indicative of survival rate or post-surgical success metrics. I have had certain patients gain weight so that we had enough fat to transfer. It is all about designing the perfect plan for You.Good luck, please let us know how it goes.-Dr. Constantino Mendieta

Unfortunately, unless you have donor fat from an identical twin, fat transfer from a donor would be unsafe and unsuccessful.  Your immune system would attack and kill the transplanted fat cells in the same process and organ transplant experiences, except organ transplant recipients take medications which many serious and dangerous side effects to minimize the immune response.

Only the fat from an identical twin can be used.  I have had very good success with thinner patients and fat transfer.  Find an expert at BBLs who performs hundreds of buttock augmentations
and who has good before and after pictures and good reviews.Kenneth Hughes, MDLos Angeles, CA

Unfortunately, someone else can't donate their fat for your BBL procedure.  This would be quite unsafe and potentially dangerous.  Your body would reject this foreign fat.

Unfortunately you can not use the fat from someone other than an identical twin. Implants or waiting to see if you gain weight at some point.

Unless you are an identical twin, the fat will not survive. It will be rejected because of lack of comptability as it would with a organ transplant unless you were taking immunosuppressives.

Unfortunately not.  Fat cells have markers on them that would tell the body that your family members fat cells are foreign.  Your immune system would reject them.  It would only work if you use the fat from an identical twin theoretically.  Some people can gain enough weight to make a BBL possible.  Discuss whether this is possible with your doctor. Best wishes.