“If you keep your opponent from winning 2 points in a row eventually you will win”
It’s not a problem to loose a point, but what often happens is that your child obsess about loosing a point, which then negatively affects the next one. After loosing the 2nd point your child gets even angrier, which then affects decision making on the 3rd point. Having lost 3 points in a row your child all of a sudden finds themselves in a downward spiral of negative momentum and THAT’S no good.
Knowing that Roger Federer has only won 55% of all the points he has played in his professional career might help put things into perspective for your child. Federer almost looses every 2nd point he plays, but most kids competing in the weekends act like they are supposed to win 2/3 of the points or more.
Maybe it’s more important to get back on track for the next point, than obsessing about the previous one. The more unrealistic expectations the more your kid is going to be troubled by their emotions. Knowing statistical realities of tennis oftentimes help kids accept the loss of points. The better they accept the natural mini-loses in a match, the better opportunity they provide themselves with to be ready for the next point.