A twо-mоnth оld boy presents for his well child exаm, but mom's primаry concern is his crying аnd fussiness throughout the day, especially in the evenings. His mother is convinced it is his milk-based formula (Similac Advance) which he has been on for the past 3 weeks as he has weaned off breast milk. Everything else on history & a complete exam is within normal limits. Answer the next two (2) questions based on this case. If the new formula for the baby doesn't make any difference in his symptoms, your next step is: