What an extraordinary story. Did your friend take her baby for an antenatal appt, or was it for a specific reason? In the first year of life, the BP of a baby rarely exceeds 100mms of Hg systolic and lower figures are quite common in normal babies. BUT Systolic figures of 44 and 56 are exceedingly low and at that level the kidneys would stop working. However I question the readings as
a) the diastilc ( 2nd figure) is higher than the first (Systolic) and this is impossible.
b) If the BP results were meaningful they would have kept her in.
c) if she is a thriving baby and the hospital appt was routine, then tell your friend not to worry.