Bullies always love to blame other people rather than take responsibly for the emotional harm they cause other people. "I was just joking" is the common reframe that excuses this action.

Myself, I work on building trust and understanding with my children. I'm not going to sell that short for a gag and I'm not going to abuse their belief in me just to make a joke. Trust and open communication is the thing that gives you a relationship with your kids for life.

It's sadistic to lie to upset someone to the point where they cry. It's worse when you laugh at them. It's even worse when you exploit that and have the internet in on your joke. They also get to point and laugh at your kids. If a school aged child did that to another school aged child it would be cyber-bullying. But somehow parents have the right to treat their children this way.

This is just mean spirited. OP shouldn't be surprised when his kids don't make the time to talk to him when they are adults. Mistrust breeds distance.