Did your baby go through separation

[ElizabethBennet]

Lots of cuddles when you can give them.

Also, start playing peekaboo and games like that with him. He'll eventually learn that just because he can't see you, that you're still around.

And time.

[pixelpassion]

Babies start to get separation anxiety at around 7-8 months, so sounds like K is right on track. Peekaboo is a good suggestion. Also, it's a good thing that K has separation anxiety with you (developmentally speaking).