How were you able to have twins? Genes? IVF? Naturally?

Stephy • 31yrs old. 10yr old boy & 7yr old girl. TTC
Hi every body! I wanted to see how many people wanted twins but known they didn't have no twin in their family giving them less chances to conceive them.
How were you able to get pregnant with twins?
Planning? Or just happened? 
Tell me your story!