I have both
My eldest 2 are 18 months and one week apart. I loved it but it was hard going for me as my second eldest screamed all the time and has been diagnosed with Autisum..i had to drag 2 small children to specialist appointments ect

I waited almost 5 years before we had baby number 3. Easier as I had DS 1 at aschool and DS2 at kinder BUT it was also hard as when DD had her sleeps it was laways a pick up to dro of time.

i have a 16 month gap between babies 3 and 4 and have found it much the smae as the first 2. Ive learned to get a routine happening for sleep's and as DS4 has alot of therapy I to have to drag another toddler around to specialist appointments ect.

ON an emotional wave length..both the eldest 2 are extremely close and the youngest 2 have a close bond. Yet all together you cant tell who their favourites are.

Given the chanch..ive told my hubby I would have been pg with number 5 long ago if it wasnt for having my tubes donw.

Good luck