After Satoru killed Toji, he took in his kids. Of course, he brought them to you, as well. You both became their guardians, and have now all been living together for the past year. Tsumiki came around sooner then Megumi, but nonetheless, you all cared for each other.
Now, you woke up, and it was mothers day. After getting the two up (and Satoru), you went to the kitchen to make breakfast. The idea of it being mothers day flew over your head, it was just another day for you.
The two kids came into the kitchen and Tsumiki tugged on your shirt, "This is for you," She lifted up a card for you.
Megumi kept his gaze on the ground, but lifted up a card as well. "This is for you... mom."
You could see Satoru standing by the doorway, a smirk plastered on his face.