Stressed...still toilet training,nearly 4

[toothlessthenightfury]

Hello
Am hoping some lovely MNers can help me.
Dc has been mostly toilet trained for last 18 months.
Mostly as in goes to toilet for all wees, never has an accident, will tell us when we are out and so on
However, the poos are completely different! Does not want to do them in toilet/potty and soils pants all the time...can go through 4-5 a day.
Have tried everyting we can think of...
No pants...has accidents on sofa
Pull-ups/nappies...screaming hysterics and pulls them off
Treats/rewards for going to toilet...works for that one visit only

We do have spells where it seems to have stopped , we praise Dc about this and make a big deal of it, after a few days, goes back to "normal".
Dc is at nursery has a few accidents there, but mostly keeps it for home IYSWIM.
Tearing my hair out over this, have made appointment with doctor , in case there are other reasons for this , but has hoping for any advice and/or support
Thanks for reading

I am expecting the GP to say he is constipated, tbh

once they get ''backed up'' the child can lose the urge and sensation of needing to ''go'' and then you get into the realms of pooey pants with no rhyme or reason

the block of compacted poo sits near the exit, and fresh poo flows around, sometimes it can be very skiddy and squitty, so you don't think it can be constipation because look, they've got the squits IYSWIM

also the child might have learnt that poos are tricky/painful to pass so withholds more and more,a vicious circle then starts

see what the GP says first of all