Sound made by babies/milestones

I am realy sorry , but i didn't now where to post this ...

It is no bug !    i just want to give a feedback /suggestion for improvement .

Topic : When the baby fulfill a milestone a massage pops up and you hear a special sound ...  this sound suggest (for me) a 'failure of a task' .

I thing it should be a     happy / light / power-giving   sound  -  don't you think ?

                                   playwell