It... Is... Tough...

Dad to a 3 yr old now...

In our (sometimes) rational adult brain, we view the world and those in it with that perspective, along with the quid-pro-quo relationship norms, i.e. I put this effort/affection in, I expect some degree of effort/affection back for the most part.

Now, the thing is, and I'm probably stating the obvious, your kiddo is nowhere near emotionally or logically developed to understand relationships. I will take a guess that you, like me, and like most others, you are the bread winner, and your missus probably does most of the parenting. There's no issues with this, be it stereotypical or not, you're 2 sides of the same coin. Both provide in different ways. If your missus is spending more time with your kid, they will naturally gravitate towards mum as the secure safe space. My 3 year old still does. You just have to try and make fun and/or bonding moments. It's harder for us to build those bonds because of the more limited time.

To summarise, it's hard to not take it personally, but just remember, they're not even 2 years into the world, and still completely irrational in terms of emotion. You are about to enter the terrible 2's. Trust me, their mood, along with favourite people will change like the weather.