If you're counting her calories together, here's a rule of thumb: if you add an extra 500 calories per day, she will gain roughly one pound a week on top of whatever else is happening. 1000 extra calories per day -> two pounds and so on. A lot of factors can affect this but it's a good estimate to start with.
You can get the calories from anywhere - fast food, home cooking, DIY weight gain shakes, etc. If she feels like she just can't eat as much as she needs to, put the calorie counting aside and just focus on stretching out her capacity. She doesn't need to stuff until bursting all the time, just extend a little bit past full as often as possible. Never any need to hurt herself or feel sick.
5 years
