Thank you for such an interesting insight into part of the Japanese culture.
Just curious, does your married status makes any difference to your participation in the ceremony at your parents home? In our Chinese culture in Hong Kong, now I'm married, strictly speaking I cannot make incense offering in my ancestral temple because I am not part of the family anymore. Whereas my husband can, maybe as a guest? (I never found out the official reason). Luckily customs are more relaxed nowadays with the passing of more traditional elderlies.