Last family reunion! Should this family be really laughing ?

This photo was shared on Reddit two days ago and has gotten over 3million views with many people finding it odd that the family was laughing heartily in the pic. Why did people find it odd when it looks like a family having a fun time together? Well, do you see the elderly man holding a card which reads "Our last family photo."? He's dying and he wanted one last family photo. Isn't it great that the family could find something to laugh about despite their situation.