Booster seat is a great idea. Or an ijea highchair without the tray up at the table....... But if that doesn't work I wouldn't worry too much about him sitting at the toddler table for a couple of months, as soon as his big enough he can sit with you. Can uou move the little table next to your dining room table? There are so many years of all sitting together at the table ahead. If sitting at his toddler table saves the tears and heartache I'd run with that for a couple of months. It's not ideal but I found it was easier than the tears.
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