Using the initials of my family. Not judged, just for fun :)
1. DH: JW
DW: OH
DS: DW
DS: KA
DS: SC
-----------
2. DH: JW
DW: GI
DD: JK
DS: GW
DS: KJ
DD: JA
---------
3. DW and JA are married:
DH: DW
DW: JA
DS: KJ
DD: KJ
---------
4. JK from the second family gets married.
DW: JK
DH: AB
--- 3 kids from previous marriage with Swedish names.
------ DD:
------ DD:
------ DD:
DD: DE
DD: MP
--------------------
KJ from the second family gets married.
DH: KJ
DW: CA
DD: KR
DS: CJ
I hope that makes sense. Have fun!