Pesach 8:8

An onein goes to the mikva and eats his pesach at night which cannot be done in other kodshim.

If you who hear about a death of a close reletive, or had others gather bones of a corpse for you, you go to the mikva and eat korbanos.

A person who became a proselyte on erev pesach, Bais Shammai says you go the mikva and bring the korban pesach. Bais Hillel says becoming a ger is like touching a corpse and you are tamai for 7 days.

Pesachim 9:1

If you are tamai or in a far away place and did not bring the korban pesach, you can bring the korban on pesach sheni. If unintentionally or due to something that prevented it, you did not bring the korban pesach on the right day, you bring the korban on pesach sheni. The difference is that if you are tamai or in a far away place and did not bring the korban pesach, if you did not bring the pesach sheni you are not punished with kares. However, if you missed bringing the korban pesach on the right day unintentionally or due to something that prevented it and you did not bring it on pesach sheni, you are punished with kares.