7-8 Week Old Kitten Not Gaining Weight

[apyles]

She was eating kmr really well and then a few weeks ago kept getting in to my other cats wet food. So I bought kitten wet food and some kitten dry food for her. She was eating it will but always seemed to throw up eventually. Its like she could only keep milk down. Now she acts like she wants to eat but doesn't eat a lot. She was up to 2 lbs but is back down close to a lb. Her stomach growls like shes hungry or its upset. She plays at times but has become more of a calm loner. Wouldn't necessarily say lethargic. She just did a number 2 that was funny and had specs of blood. Not sure if that's due to straining or hook worms. I know kittens get roundworm from their mothers and I read somewhere that the more the roundworm grow and multiply, it can cause vomiting and loss of appetite. Like I said she acts like she is starving when I put my other cats wet food down. Any advise? Trying to get her in to the vet today as well

 

[StefanZ]

This is clearly time to visit the vet. Deworming done? If not do so.

Goats milk is good, you can have some dextrose sugar in it to give more calories.
Try also with mixing in egg yolk, raw if there is no salomonella in eggs at your place, boiled if there is.