It would depend on the circumstances of the regurgitation and the resources at hand in dealing with it. If this were to occur while in church, one need only alert a priest, deacon, extraordinary minister of holy Communion, or an usher (assuming that no one has already noticed the incident) and ask that person to take care of it. Given that the ill person would not be in much of a condition to deal with the problem alone, this would be the ideal solution.
If one has regurgitated over fifteen minutes after consumption of the Eucharist – the general amount of time the Real Presence is believed to remain after consumption – one could simply clean up the mess or ask someone else to assist you in doing so. There would be no need to sort through the mess looking for pieces of Communion. Only if it is obvious that one has regurgitated pieces of Communion and there is no one around to help should one try to rescue the pieces of Communion and take them to a priest or deacon for proper disposal.
Perhaps your daughter’s reaction was because she is a bit overwhelmed at the idea of looking through vomit for pieces of Communion. Presuming that this was a hypothetical situation you posed to her and that the conversation was not the result of an actual incident to which she needed the information, this is a good reason why it likely was not a good idea to discuss with a young child a hypothesis unlikely to occur in real life. Even if she had asked about the situation, it may have been best simply to tell her to come to you or to approach a priest or deacon for help in the improbable event such an incident should occur.