Thanks everyone for the information. The Additude link was very helpful. Dad is sending a high energy protein shake (generic from WalMart). Grandson likes the taste and hopefully it will help, time will tell with that. Not real happy with what mom is sending and she now has him for several days and will be going back in for weight check in a couple of weeks so will see what weight is.
what dad is hearing mom feeds him more snacks than the high protein calorie foods but nothing can be done about that. Once again thanks for the information