If a parent reports interest expense of $4,300 with respect to bonds held intercompany and the subsidiary

Question:

If a parent reports interest expense of $4,300 with respect to bonds held intercompany and the subsidiary reports interest income of $4,500 for the same bonds,
(a) Was there a constructive gain or loss on the bonds?
(b) Is the gain or loss attributed to the parent or the subsidiary? and
(c) What does the $200 difference between interest income and expense represent?