My wife and I have an almost 2-year-old daughter, whom since the age of about 6 months, cries when we laugh.
For the first approximately 6-9 months, this was pretty much every time we laughed. Since then it's usually only when she's sensitive (i.e. overtired, hungry, etc.).
The scenario is usually:
- all sitting at a dining table
- wife and I discussing something
- one of us laughs or starts chuckling (we aren't loud!)
- daughter looks at the person that started laughing
- her face goes bright red, mouth open, expression of "horrified", starts crying
- when she's able to speak, says things like "mummy/daddy not laugh" but can't tell us much else about what's happening for her
From about 14 months she's developed a lot of language, and seems to understand intellectually when we explain "laughing makes me happy", "it's OK to laugh", etc. with vigorous head nods. This can also help to calm her down. However another laugh causes the emotions to override all logic.
It feels to us like she thinks we are laughing at her, but who knows. It rarely happens when other people laugh. She can laugh and that's OK but sometimes when we laugh back she gets upset again.
Apart from this behaviour, she seems to behave like a "normal" child of her age. We have seen her develop phobias when something has really scared her but so far they've never lasted longer than a few months. Maybe repeated laughing is repeated exposure so she can't get over it?
As this has been going on for so long (not to say we'd like to be able to freely laugh in our own home!), we're not sure if there is something more serious going on that we should pay attention to. Or if there's something more we can do to help her.