Gut pro, klair therbiotic, VSL3 are all good multi strain probiotics with high CFU. With probiotics, one should rotate. Some of these have clinical studies on efficacy but hard to say what is going to help, so just need to keep trying. I would avoid probiotics that are soil based and form colonies (these have efficacy with respect to constipation but not natural for these to be in the gut). Do some stool testing to get an idea on the various strains.

I have tried Serenity and in tune down the spine for agression/anxiety and focus. I think they take the edge off of the aggression, especially in my 4 year old. For him they work in a matter of minutes, he is way less negative and angry. He told me that he can feel a difference and he will often come and tell me if he needs more oils. I'm not sure if they have done a lot for my 11 year old, but I don't see him pulling his hair as much when I use the oils. I have also used balance oil on the bottom of their feet.

Before trying various probiotics have you considered a pediatric gastroentomologist? We see one and it was the only thing that helped my son. He would withhold going for up to 10days!!!! Miralax, fiber gummies, and fruit are your friends:)

I meant to say also, that digestzen is helping with the extreme constipation my kids have too. It comes in soft gels and works really fast.

I just got vetiver and am going to try it as well. I have had wonderful results with the other oils I've tried. I hear that vetiver is another good one for spectrum and adhd. I have also tried cedarwood for night time, and it is helping my guys sleep.