The quote essentially brings out how the feelings of remembrance and loss can intermingle with one another.  In the particular context, the wake of Junior's grandmother is a moment where there is intense sadness for the passing of such an important and sincerely loved woman.  However, when Junior's mother's revelation scares off Ted, the sight of the White men running away, is something that grandmother would have appreciated.  In the process, the reminder of her spirit and its collision with her departure helps to make this moment one where laughter and tears are interchangeable.  The glory of one's past and the pain of their loss helps to create an almost awkward, yet beautiful dualism within one who mourns.  The sadness of their loss felt on a personal level cannot overtake the joy one experienced in their presence.  In this, Junior's assessment of how "laughter" and "tears" are similar is evident when considering the loss of Junior's grandmother.  The experience of death in the community is one where someone might not necessarily have gone, but rather moved to another place, requiring a reaction that is not entirely rooted in sadness, but contains it.