使用Akka Typed时，在Actor生成过程中发送消息需要注意一些细节。下面给出一个示例代码来说明。

首先定义一个Actor协议：

object MyActorProtocol {
  sealed trait Command
  case class Start(replyTo: ActorRef[String]) extends Command
}

然后实现MyActor，它在生成过程中会发送一个消息给它的子Actor：

object MyActor {
  def apply(): Behavior[MyActorProtocol.Command] =
    Behaviors.setup { ctx =>
      val child = ctx.spawn(childActor(), "child-actor")
      ctx.log.info("Child actor is initialized and is ready to receive messages.")
      child ! ChildActorProtocol.MyMessage("Hello, child actor!") //在生成过程中发送消息给子Actor
      Behaviors.receiveMessage {
        case MyActorProtocol.Start(replyTo) =>
          ctx.log.info("Received start message.")
          replyTo ! "Starting actor."
          Behaviors.same
      }
    }
}

private object childActor {
  def apply(): Behavior[ChildActorProtocol.Command] =
    Behaviors.receiveMessage {
      case ChildActorProtocol.MyMessage(msg) =>
        println(s"Received a message: $msg")
        Behaviors.same
    }
}

在启动MyActor时，需要指定一个ActorRef来接收MyActor发送的消息：

object Main {
  def main(args: Array[String]): Unit = {
    val system = ActorSystem(MyActor(), "my-actor-system")
    implicit val timeout = Timeout(5.seconds)
    implicit val scheduler = system.scheduler
    implicit val ec = system.executionContext

    val responseFuture = system.ask[String](MyActorProtocol.Start).mapTo[String]
    val response = Await.result(responseFuture, timeout.duration)
    println(response)

    system.terminate()
  }
}

在MyActor生成过程中发送消息时，需要保证子Actor已经被生成并处于可用状态，否则可能会因为Actor路径未找到而抛出NullPointerException异常。