Why do forwarded emails show on iphone(iOS) but not iMac (OS)

While collecting relevant info for family vacay, I asked my daughter to forward an email from Disney to me about her reservation, etc. After receiving email, I dropped it in a folder in MY Apple mail (which is what she uses too). Just checking on iMac today and I see nothing but a header for the forwarded email. I doubled checked on iphone and see it completely. As I now recall, this same thing happened a year, or so, ago. We all have updated software. Any ideas why I don't see the forwarded email on iMac?