Back/sciatic nerve pain

Alisha • I'm a stay at home momma of 3, this is my 4th pregnancy and can't wait to welcome our new little into the world!
I am 12w5d right now and this is baby number 4. During my 2nd pregnancy I started getting really bad back and sciatic nerve pain that ended up with me having to go and do physical therapy during pregnancy. It came back with my 3rd pregnancy but not until later on, well with this pregnancy it has already started! Is anyone else going through this? Any suggestions to help alleviate it?