Put the soap bubbles on yr hear and make funny faces. Make it funny! Usually, after this phase, it comes the one where he does not want to get out and screams because of that hehe. My son is 3 y and half, he just stopped complaining. Aaah parenting! Just keep trying! Eventually, he is okay. Could also fill the bath and just stand beside it and playboats with no mention of getting in. Then subtle convince him bathing in the game.
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