An insider talks about the "seamless" relationship between the comedian and his girlfriend's family.

The SKIMS tycoon — who shares four youngsters, North, Saint, Chicago, and Psalm West, with ex Kanye West

 is "thankful" for the previous Saturday Night Live star's bond with her children,

"Pete and Kim's relationship has become more serious, and Kim feels entirely open to permitting Pete to be around the children 

 invested a great deal of energy with them as of late," the source said. 

 "Kim would have rather not constrained anything and loves that it has been a characteristic movement. 

When Davidson spends time with her kids, the insider added,  

"It takes a lot of stress off of her and their relationship.