Yep brushing with them is certainly effective, as kids learn by example. We made up a song we sang, watched videao’s about brushing teeth, bought an interesting timer, electrical tooth brushes and a week book named “Karius and Bactus” which is an adorable wee book about a wee boy who doesn’t want to brush teeth

I’ve found the best way to encourage children to brush their teeth is to do it with them, my toddler does it when his big sister does hers. We try to make it fun.
I make started brushing their teeth as soon as they had teeth, I also brought the baby chew tooth brush while they only had gums.

Do it together at the same time works for us

On cardboard, draw little dinosaur footprints and contact to your bathroom floor and to floor outside bathroom if not carpet. So a footprint fun track leads to bathroom sink. For your child to follow. I guarantee if you stick these down when they not around then when they see them they will follow the trail. Let them know it’s for brushing their teeth!

I have a reward chart for my son it has been working really well. He still doesn’t do it twice a day every day but he has improved a lot.

Try a reward chart with a weekly treat for brushing everyday

I couldve written the same question, both my kids are very hit and miss, my son had a dentist come to school a few weeks back, they gave the kids a chart which has 4 weeks with morning and nights on them, I’ve told my 2 if they can do a whole week they’ll get a reward, we are on week 3 and still haven’t done a full week, but they have improved