I changed the light bulbs in my house to calm my worries. But there is one nail that is stuck and cannot be removed, so the old light bulb remains hanging next to the new one. In our family group chat, we also have a nail that cannot be pulled out. It is the person we cannot invite to join the group chat, Ms. Kyung-hee, also known as our 'mom'. Amidst all this, we are about to have a new family member.