If it was from the same side of the family tree, then yes, the child could end up having a higher percentage of measurable SSA than either parent. Genetic inheritance isn’t a perfect science however (avoiding long complicated explanation here), so if there are any no-calls or sequences otherwise getting broken apart into segments too small (less than 5cMs) to register then the hypothetical child could seem to have less of that heritage than either parent.
However, I’ll reiterate that the fact the testing was done through AncestryByDNA means the results are not up to current industry standards and therefore I’m not willing to speculate on how much SSA this guy actually may have in his heritage.
Edit: html issue
