Is there any way to query child and grandchild concepts in SPARQL

Hello everybody.

I have 5 concept: concept A is a father of concept B, and concept B is a father of C, the same with C and D, D and E... In my example, you can imaginge this:

E rdfs:subClassOf D
D rdfs:subClassOf C
C rdfs:subClassOf B
B rdfs:subClassOf A

I wondered how to query all child and grandchild of concept A, in this case is B, C, D, E in SPARQL and Allegrograph.

You should check out SPARQL 1.1 property paths. For example:

SELECT ?children
   ?children rdfs:subClassOf+ :A .

You need a version of AllegroGraph greater than 4.4 to support SPARQL 1.1.