Sheils, his sister 2-year-old Matilda, and their mother Katie Seley were swept away in the flash flooding that submerged sections of Bucks on Sunday, July 16, Daily Voice has reported.
Seley and five other adults were found dead during the initial search that Sunday, police said at the time, but Conrad and Matilda remained the focus of a county-wide recovery effort for the week following.
Matilda's remains were found near the Delaware River on Friday, July 21 some 32 miles from where she was lost in Upper Makefield Township, authorities said last week.
Upper Makefield police announced Wednesday, July 26 that the search for Conrad was over.
"At this point, we have exhausted all means of attempting to locate Conrad," the department said in a statement. "With broken hearts, we regretfully announce that the active search for Conrad has concluded."
The surviving Sheils family members have been made aware of the decision and "express their deepest gratitude for all those involved in the search efforts," police said.
Police said they had been searching for the 9-month-old near and along the Delaware River, both on the Pennsylvania and New Jersey sides, using "drones, boats, K9s, divers, sonar, air assets," and hundreds of first responders.
Those efforts proved fruitless, the department said.
"Like all of you, we are truly heartbroken and saddened," UMTPD wrote. "Although, at this time, we were unable to reunite Conrad with his loving family, he will forever live in our hearts and he will never be forgotten."
Seven people in total were killed by the flooding, police said.
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