Baby no4 3rd baby is 14wks old

Currently 4wks +2.
Delighted to be blessed again with our 4th child we want to complete our family & keep the gaps small. Anybody any experience with planning there family like this, are your children close?
Another query I have has anybody had a baby this close to there last pregnancy how did you feel, nervous of the pregnancy sticking?  We want a  family of 5 kids, currently have 3 healthy boys 1st age 6 born at 24wks gestation 1lb9oz, 2nd age 4 born @ 40+4 3rd now 14wks &3days old born @ 41weeks. Break in between 2nd & 3rd to save for a wedding & get married. Due now April 8th 2016