When do I start weaning kittens?

One of my kittens decided to change mother?

• i have 2 queens and their respective litter of kittens. Stripes has 6 kittens 3 weeks old and Sardine has 4 kittens 5 weeks old. One of Sardine's babies decided to move to Stripes nest, she is ok with it as she is nursing her too like her other babies. The problem here is that those kittens are in different "stages" of development/behavior. The older ones already go to the litter box and they eat some canned food while being nursed too. The kitten who has moved used to eat too and go to the litter box, now she is receding and only wants to be with Stripes all the time. She seems to not be interested in solid food anymore as she doesn't play with her brothers anymore (instead, she beats the new brothers which are too young to start playing with her). I don't know if this is good for her weaning process..

• Answer:

  my mom had 3 cats and they all had there first litter in the same week, the kittens would sometimes switch between moms, just make sure the little ones can still get in there and nurse