So today I moved my two sims in with one another and that included their two dogs. My two sims both have 100% relationships with their dogs but whenever I get one of them to 'encourage breeding with...', the dogs go up to one another and start growling at one another. They also get bubbles above their heads with the other dog's face crossed out.

I thought it was because the dogs haven't gotten a high enough relationship together yet, but when they're around one another they both get love hearts and are really friendly together. Their traits are compatible too.

When I have done this failed 'encourage breeding with...', the sim who encouraged it gets a sad moodlet for 'rejected encouragement' or something (I can't remember what it was called off the top of my head). The female dog then has the option for mating greyed out and it says she's already mated and to check back to see if it worked... but she hasn't mated.

The lot also has the breeding trait and my sims are encouraging the dogs to be friendly to one another.

I repaired my game but it didn't do anything. I'm so confused. I'm thinking it's a bug of some kind? Unless the dogs just need to build their relationship up or something.

I had the same problem for the longest while. They need to put some kind of disclaimer that breeding, while not impossible, can fail multiple times over but still succeed if you give them enough time between attempted mates (a day or so) and keep encouraging over and over. Went so far as to get the controllable pet mod. Given the dogs relationship is completely hidden (if it is even coded to exist) it is basically a roll of the dice.

Mind you I did succeed with mating a pair where one dog was aggressive and they did fight. So even if they hate one another a mating IS POSSIBLE!

Moved to help