It is generally recommended that parents who disclose should do so in age-appropriate ways, ideally starting well before the age of five with a discussion of the fact that their parents needed help to have a child because certain things are needed to make a child—namely, sperm and eggs—and because the parents did not have one of those things, a nice woman gave it to them. Families sharing same donor
Having contact and meeting among families sharing the same donor generally has positive effects. It gives the child an additional extended family and may help give the child a sense of identity by answering questions about the donor. It is more common among open identity-families headed by single men/women. Less than 1% of those seeking donor-siblings find it a negative experience, and in such cases it is mostly where the parents disagree with each other about how the relationship should proceed. Other family members
Parents of donors may regard the donated eggs as a family asset and may regard the donor conceived people as grandchildren. Donor marketing
For a donor to be accepted by an agency and repeatedly used she must be marketable and appealing to the recipients. Although egg donation is a significant, life-giving act, the companies participating in this industry still have to operate with an economical mind-set. Matches between egg recipients and egg donors are what make the profit for the company and achievable to continue these processes for others.
It is possible Neanderthals might have used "hmm". Nicholas Christenfeld, a psychologist at the University of California, San Diego, and an expert on filled pauses, attests "hmm" is popular largely since its such a neutral sound and that "its easier to say than anything else". The earliest attestations of "hmm" are from Shakespeare, "I cried hum... But markt him not a word" (1598 Shakespeare Henry IV, Pt. 1 iii. i. 154). It may be a vocable that grew out of lexicalized throat-clearing. Use as a filler word
"Hmm" is a "filler" word, such as "um" and "er". Use of "hmm" for "filled pauses" has been considered by many as stupidity and showing a lack of skill or competence, but many linguists  attest this judgement is unjustified. Typically, "hmm" is uttered when the person is being especially conscious about whom they are talking with, and as a result are thinking deeply about what to say. Moreover, the use of "hmm" is often interactional and cognitive. The interactional function is to do with politeness: if someone is invited to a party and responded "no" without a filled pause, they might appear rude, but a reply of "Hmm, sorry, no" might appear much more polite, as it seems the speaker is giving the offer some thought, rather than abruptly declining. Thoughtful absorption
The use of "hmm" is typically used during "thoughtful absorption", which is when one is engrossed in their flow of ideas and associations, that lead to a reality-oriented conclusion.