Kissing a child in shul during davening is not allowed.
Back in the days when my oldest child was quite young, I had her with me in shule on a Friday night. Someone came over and told me that kissing a child wasn’t allowed, which was fine – I didn’t know that, and I learned something. It also allowed me to tell the person, a notorious talker during davening, that talking during davening was also not allowed. Unfortunately, his reaction was quite unlike mine – he got very angry, mumbled something under his breath, and walked away.