• reister,
• rezister,
• reesister,
• reseister,
• resister,
• resyster,
• re sister,
• ee sister,
• de sister,
• fe sister,
• te sister,
• 5e sister,
• 4e sister,
• rw sister,
• rs sister,
• rd sister,
• rr sister,
• r4 sister,
• r3 sister,
• re aister

The plural form of the word "re sister" is "re sisters"

The singular form of the word "re sister" is "re sister". This is because "re sister" is already a singular noun.