(CNN)The US is on track to encounter more than 2 million migrants at the US-Mexico border by the end of the fiscal year, according to internal government estimates reviewed by CNN, marking a record high.Here’s what’s happened this week: Harris diving into migration diplomacy. The Vice President and her team are staring down attempts to make her the face of the Biden administration’s response to the crisis at the border, a little more than a week after being assigned a role that positions her in the center of one of the administration’s most divisive issues. Video shows children being dropped from border wall. Border Patrol agents rescued two young Ecuadorian sisters after alleged human smugglers dropped them over a 14-foot-tall border fence in the New Mexico desert, the US Customs and Border Protection announced in a news release. ‘Serious concerns regarding detainee care.’ Detainees at an Immigration and Customs Enforcement detention center in Arizona filed hundreds of grievances about mistreatment, including use-of-force incidents, according to a watchdog report, which concluded that violations threatened the health, safety and rights of those at the facility.Keep an eye on this bipartisan bill. Key House lawmakers introduced bipartisan legislation that would address repeated funding and resource shortfalls that occur during large upswings in the number of migrants arriving at the US-Mexico border.