We think that Kylie Jenner was just trying to piss off Blac Chyna with this Snapchat!

The teen posted a rare photo with her boyfriend Tyga's young son on Snapchat on Wednesday -- and of course we have a feeling King's territorial mama wasn't loving the fact that her son was used to help Kylie's social media stats.

In the mirror selfie, the 19-year-old reality star donned an oversize pink T-shirt while the 3-year-old hangs out by her side, looking oh so adorable.

At first it looked like Ky was babysitting King on her own -- but luckily it appears as if the reality star and her beau were watching the wee one together. The bootylicious starlet also posted a photo of Tyga giving her a piggy back ride.

Umm hey Kylie, King Cairo's the one who's supposed to get the piggy back ride -- not you!